20w50 instead of 5w50, 5w40, 10w50 - mistake?

Discussion in 'The Garage' started by Weird Bug, Jul 8, 2013.

  1. Weird Bug

    Weird Bug Weird BUG

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    I just changed the oil and filter on my 2011 BMW R1200R (oil/air-cooled camhead boxer) and used my Amsoil at 20w-50. I used that brand and weight in my Ducati (was recommended) and if I remember correctly in my 2006 GS and 2007 RT.

    Then (duh!:puke1), I noticed that the manual calls for the 5w and 10w weights listed above for >=20c temperatures. The manual states that these are "generally admissable viscosity classes." I guess I should not have assumed!

    I'll be heading out Friday on a two-week trip to the Midwest (4,000= or - miles); it'll be hot and the bike will be running hundreds of miles each day (i.e., unlikly more than one cold start up each day).

    I was contemplating changing the oil out to the proper weight, but thought I'd pose the question here first. I know it may start another "oil thread", but I did think this was a unique question. Would any of you recommend changing it out to get to the recommended first weight? Easy to do as I'd keep the filter on and only do the drain plug. Cost isn't great, but...
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  2. OTB

    OTB Oh fer Chrissakes

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    20w-50 is the standard oil weight for my 07 R1200r.
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  3. nevermind

    nevermind sLOW Rider

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    You are fine. Rock on. Ride on. :deal The first number is the cold temp viscosity. The second number will be very nice on your motor for this ride and I doubt you will get into near freezing temps on your ride. Unless of course, you venture off course and wind up on the N. Pole.
    #3
  4. Benesesso

    Benesesso Long timer

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    5W-XXX (greater number) is very thin 5 weight oil that is loaded with additives to prevent it from thinning so much with temperature increases, such that it is as thick/viscous at elevated temps. as the second number.

    After X number of miles/hours, those additives start to become less effective, so you can end up with something like 5W-10 (or worse) than the 5W-40 you poured in. With 20W-X, additives are not required to keep it at 20 weight (hot), although your 20W-50 could end up as 20W-20 if you lose the additive effect.

    I don't run thin oil, but I keep the revs low until the engine is fully warmed up. :1drink
    #4
  5. Weird Bug

    Weird Bug Weird BUG

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    Yes, thanks guys. Sometimes one can overthink these things:cry and I appreciate the reassurance.

    On the cold temp startup, again - it will be started once in the morning and be warm all day. So, this oil and motor will be cold started maybe 20 times before it gets changed upon return. Many bikes will get started hundreds of times in this amount of miles (no one on this forum of course!).
    #5
  6. Weird Bug

    Weird Bug Weird BUG

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    Always my practice!

    Thanks for the good information.
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  7. Motomantra

    Motomantra Registered Lurker

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    Good advise everyone. I might add that when I first start any of my vehicles, I don't rev it at all. Allow the oil to circulate completely before touching throttle.

    On the subject of viscosity range; remember the wider the range the more viscosity improvers are added. The more that are added the sooner viscosity breaks down.
    Send a sample to Blackstone for analysis.
    #7
  8. Weird Bug

    Weird Bug Weird BUG

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    You just reminded me of my second mistake. Really not a mistake, but forgotten item. I had my oil sample bottle ready and then forgot to take a sample:eek1 Must be the heat and humidity - or the fact that I need a vacation!
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  9. Motomantra

    Motomantra Registered Lurker

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    You need a vacation. DO IT.
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  10. Weird Bug

    Weird Bug Weird BUG

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    My head is already gone, but the body and bike remain here until Friday. However, the feeling that you get when you walk out of the work place, throw the leg over the loaded bike, and start 'er up is awesome:clap
    #10